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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands tagged expansion from sorted by
Terminal - Commands tagged expansion - 6 results
command ${MYVAR:+--someoption=$MYVAR}
2015-11-04 19:47:24
User: pdxdoughnut
Functions: command

See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

bind '"\C-e":"\eb `which \ef`\e\C-e"'
2011-01-26 16:11:52
User: jennings6k

Tested with bash v4.1.5 on ubuntu 10.10


as written above, only works for programs with no file extention (i.e 'proggy', but not 'proggy.sh')

because \eb maps to readine function backward-word rather then shell-backward-word (which

is unbinded by default on ubuntu), and correspondingly for \ef.

if you're willing to have Ctrl-f and Ctrl-g taken up too , you can insert the following lines

into ~/.inputrc, in which case invoking Ctrl-e will do the right thing both for "proggy" and "proggy.sh".

-- cut here --



"\C-e":"\C-f`which \C-g`\e\C-e"

-- cut here --

rm *.txt <TAB> <TAB>
2010-11-04 13:58:15
User: boschi
Functions: rm

alternative for "echo rm *.txt". Just doubletab the command you are willing to use and it will show you the affected files.

echo rm *.txt
2010-10-27 07:26:26
User: alperyilmaz
Functions: echo rm

if you're using wildcards * or ? in your command, and if you're deleting, moving multiple files, it's always safe to see how those wildcards will expand. if you put "echo" in front of your command, the expanded form of your command will be printed. It's better safe than sorry.

setlocal enabledelayedexpansion
2010-08-10 12:26:43
User: Marco

Usually the MS-DOS cmd.exe processes in the whole FOR loop as one command and expands each var like %varname% in before (except the loop var of course).

This command enables expansion of other vars than only the loop var during the FOR loop. The syntax of the var to expand is then !varname! inside the FOR loop.

Use command


to end the setlocal command.

E.g. (only works from batch files, not from commandline directly):

@echo off

setlocal enabledelayedexpansion

FOR %%A IN (*) DO (

set file=%%A

echo !file!



echo ${fullpath##*/}
2010-07-21 22:35:29
User: quincymd
Functions: echo

Quick method of isolating filenames from a full path using expansion.

Much quicker than using "basename"